package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

//检查用户是否已经完成登录
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;

        //1. 获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        String[] urls=new String[]{//不需要处理的请求路径
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",//移动端发送短信
                "/user/login",//移动端登录
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

        //2. 判断本次请求是否需要处理
        boolean check=check(urls,requestURI);

        //3. 如果不需要处理，则直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1. 判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            Long empId=(Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);


            filterChain.doFilter(request,response);
            return;
        }

        //4-2. 判断登录状态，如果已登录，则直接放行(移动端)
        if (request.getSession().getAttribute("user")!=null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId=(Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);


            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //5. 如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    //路径匹配，检查本次请求是否需要放行
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match=PATH_MATCHER.match(url,requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
